Composite wood-pulp sheet.



J. P. LEWIS, DBC'D.

H. S. LEWIS, ADMINISTRATOR.

COMPOSITE WOOD PULP SHEET.

APPLICATION FILED Nox/'.19l 1906.

11,068,9@L Patented June 3, 1913.

Z/'gnessem MDW A zgorzgg/S.

` UNITED STATES PATENT OFFTCE.

JAMES P. LEWIS, 0F BEAVER FALLS, NEW YORK; 'HARRY S. LEWIS ADMINISTRATOR0F SAID JAMES P. LEWIS, DECEASEID.

COMPOSITE WOOD-PULP SHEET.

Application filed November 19, 1906.

To all whom it may concern.'

Be it knoiwn that I, JAMES I). Lnwrs, a citizen of the United States,residing at Beaver Falls, in the county of Lewis and State of New York',have invented a new and useful Improvement in Composite lVood-PulpSheets, of which the following is a specification.

This invention relates to a composite sheet made up of several sheets orlayers of wood pulp cemented together and has the object to produce asheet which is smooth and attractive in appearance, strong and durableand which does not warp, buckle or other'- wise change its shape in use,thereby enabling such sheets to be successfully used for a variety ofpurposes, for instance, for cover ing the walls of buildings instead ofplaster.`

Composite sheets in which the several sheets or layers are all made ofthe saine kind of wood pulp are unsatisfactory in use and do not retaintheir shape but warp or buckle. I have found that by making the innerlayer of such a composite sheet of poplar pulp and the outer or facelayers of spruce pulp this difficulty is overcome and a composite sheetis produced which will retain its shape under the varying conditions ofuse and remain staight and flat and present smooth surfaces.

In the accompanying drawings: Figure l is a sectional perspective Viewof a three ply sheet. Fig. 2 is a similar view of a fiveplay sheet.

Like letters of reference refer to like parts in both figures.

A represents the outer or face layers formed by sheets consisting ofground spruce pulp, and B represents the inner layer formed by a sheetconsisting of poplar' pulp.

In The three-ply sheet, represented in Fig. l, a single central layer Bof poplar' pulp is combined with two outside or face layers A of sprucepulp. In the live-ply sheet, rep-- resented in Fig. Q, two inner layersB `of poplar pulp are combined with an intermediate layer C of sprucepulp and two outer or face layers A of spruce pulp. In each case theinner layer or sheet of poplar Specification of Letters Patent.

y Patented June 3, 1913.

Serial No. 343,968.

pulp is flanked on both sides by sheets 0r layers of spruce pulp.

Poplar pulp is comparatively fine, has a short fiber and produces a.sheet which will not warp or buckle but which is rather brittle and hasa fuzzy surface too soft for the outer or face layers of the board.Spruce pulp has a longer ber and produces a strong sheet which has asmooth tough surface and is suitable for the surfaces of the compositesheet but liable to warp under atmospheric changes. The sheets areformed of these two kinds of pulp in any usual or suitable manner andare then cemented or pasted together in the described order, preferablyby a cement containing silicate of soda. The composite sheets soproduced has smooth hard face sides, is strong and durable and does notwarp, buckle or otherwise change from its true straight or flat shape.These qualities render the composite sheet particularly suitable forcovering or facing the interior walls of buildings as a substitute forwall plaster', and constitute a wall covering or facing which is morequickly and cheaply applied than plaster, since these sheets are quicklycutl to the desired size and secured by nails or tacks, and whichretains its shape well and is sufficiently strongr to stand all ordinaryusage, and which can be ornamented by painting or papering in the mannerin which the interiors of buildings are usually treated.

As usual in wood or pulp sheets, there is a definite or similar generalarrangement of the fibers, or grain, throughout the layer, andpreferably the sheets or layers of the composite board or sheet are soarranged that the grain of the poplar layer or layers will runcrosswise, or at angle relative to that of the spruce sheet or sheets.Such relative arrangement of the layers or sheets gives even betterresults than are obtained when the grains of the several componentlayers or sheets have the same general direotion.

claim as my invention:

l. A composite wood pulp sheet consisting of separate outer and innersheets cegag 1,063,941

mented together, the outer sheets beingv formed from Wood pulp having along tough ber, and the innerl sheet being formed 'from Wood pulp havinga short hard fiber, substantially as set forth.

2. Afeornposite Wood pulp sheet consisting of separate outer and innersheets cemented together, the outer Sheets being formed from spruce pulphaving a long y hard ber, substantially as set forth.

Witness my hand, this 31st day-0f October, 1906.

' JAMES P. LEWIS. Witnesses:

HARRY S. LEWIS, E. A. VAN NESS.

